Process for removing fat prom raw wool or analogous materials by the



UNITED STATES" PATENT OFFICE.

FRANZ KOCH, F GfiRIJITZ, GERMANY, ASSIGNOR, BY MESNE ASSIGNMENTS, 'TOTHE CHEMICAL FOUNDATION, INC., A CORPORATION OF DELAWARE.

v PROCESS FOR REMOVING FAT FROM RAW W'OOL OB ANALOGOUS MATERIAIiS BY THEAID or FAT SOLVENTS.

No Drawing.

To all whom it may comm Be it known that I, Dr. FRANZ Koorr, engmeer, asubject of the German Emperor, and a resident of Gorlitz, in the Kingdomof Prussia, German Empire, have invented an Improvement 1n Processes forRemoving Fat from Raw lVool or Analogous Materials by the Aid of FatSolvents, of which i the following description is a specification.

This invention relates to anovel process for eliminating or removing fatfrom raw wool or analogous materials. The inventlon Wlll best beunderstood from the following description of one manner of carrying 'itinto effect, the scope of the invention being more particularly pointedout in the appended claims.

The organic fat solvents heretofore used for the removal of fat from rawwool or analogous materials all had this disadvantage that, owing to theremoval of fat from the individual fibers being carried too far, thetreatment was liable to render the ma.-

terial brittle whereby its value was apprecip abl impaired.

11 the case of raw wool, for example,

I from which after the removal of the yolk or wool fat the sweat excretamust also be eliminated or removed, the fibers in addition to theliability of becoming brittle also tend to turn yellow as a result ofthe penetration of the sweat lye or liquor into the cavities existing orthus produced in the individual fibers.

The resent invention is based upon the knowle go that some chlorinatedhydrocarbons of the fatty series and more particularly ethylenedichlorid and trichlorid, possess the wholly unexpected and usefulpropert of dissolving to a very small extent on y the fatty and waxlikesubstances which are present in the interior of the fibers either as anatural result of growth or from having subsequently penetrated therein.For example, wool can be treated for a long time with hot ethylenetrichlorid Without impairing the pliability of the fibers by reason ofthe drying up of the fat. It will of course be understood that in orderto obtain the best results, the temperature and the duration of thetreatment must be regulated in accordance with the nature of the solventand the nature ofthe fibrous material treated. The ready solubility andmiscibility of the fatty substances in question enable the fat to beSpecification of Letters Patent, Patented Nov. 9, 1920. .Applieationfiled February 3, 1914. Serial No. 816,391.

speedily removed or eliminated at low'tem peratures. Extremes of timeand of temperature,"therefore, play no part in the tech nical orpractical execution of this improved to the fact that while thesesolvents dissolve the fat or oil that is upon the outer surface of thefibers, they, owing to their high specific gravity and molecular weight,do not penetrate into the microscopical interstices and the interior ofthe fibers.

The use of these substances substantially in accordance with any one ofthe usual; fat removing and washing processes by the aid of chemicalsolvents in which the recovery of the means employed is aimed at,furnishes a really effective method for freeing fibrous materials fromfat. By means of the present invention, the yolk or wool oil can beremoved from the surface of the raw wool fibers without previouslylixiviating'the sweat excreta and in such manner that the removal ofsuchimpurities as are soluble in water and others can be effectedwithout the use of soap or soda. That is to say the present inventioncontemplates more particularly the use of ethylene dichlorid ortrichlorid as solvents without the addition of soap, soda or otheragents for emulsifying the solvent or rendering it soluble in water. ashas been commonly done heretofore. The use of the solvent in this mannerrenders its recovery after use a comparatively easy matter. Where thepresent invention is used there is no tendency whatever of the wool to.turn yellow and the wool retains to the fullest extent its natural fator oil and its original pliability.

It will be apparent that the chlorinated bodies referred to can be usednot only for all kinds of wool but also for all fibrous and analogousmaterials such as cotton waste, hair, feathers, bristles and the likefrom the outer surface of which it is desired to remove waxy or fattysubstances while allowing substances of the same kind that may bepresent in their interior to remain there.

flow of ethylene dior trichlorid is then conducted through the wool,whereby the soluble constituents are dissolved. \Vhen all solubleconstituents have been removed the chlorinated hydrocarbon is drawn oif.Preferably the wool is then rinsed with fresh dior trichlorid ofethylene, and then by the introduction of steam or hot air the solventadhering to the wool may be evaporated and, if desired, reclaimed.

From the foregoing it will be seen that the present process possessesmany advantages over those heretofore used. By mixing these chlorinatedbodies with other tat solvents of lower specific gravity, the specificgravity and the cost per unit of Volume may be reduced. The propertiesof such a mixture will represent approximately a mean of the propertiesof the different constituents according to the proportions in which theyare used.

Claims:

1. A process for removing fat or oil from raw wool or similar fibrousmaterial, characterized by treating said fibrous material with achlorinated hydrocarbon of the fatty series as the solvent, in theabsence of soap, soda or other agent for emulsifying the solvent orrendering it soluble in water.

2. A process for removing fat or oil from raw wool or similar fibrousmaterial, char acterized by treating said fibrous material with ethylenedichlorid, in the absence of soap, soda or other agent for emulsifyingthe solvent or rendering it soluble in water.

In testimony whereof I have signed my :iame to this specification in thepresence of two subscribin witnesses.

. .%R. ING. FRANZ KOCH. lVitnesses ALBERT PAUL, IDA PAUL GEB. KOCH.

